Use `lexical-binding` in all `lisp/international` files

Use `lexical-binding` in all `lisp/international` files

* lisp/startup.el (keyboard-type): Make obsolete and lex-bound.

* admin/unidata/unidata-gen.el (unidata-gen-file)
(unidata-gen-charprop): Mark the generated files to use lexical binding.

* lisp/international/isearch-x.el: Use lexical-binding.
(junk-hist): Declare locally.

* lisp/international/iso-cvt.el:
* lisp/international/utf-7.el:
* lisp/international/robin.el:
* lisp/international/ogonek.el:
* lisp/international/latin1-disp.el:
* lisp/international/kkc.el:
* lisp/international/kinsoku.el:
* lisp/international/ja-dic-utl.el: Use lexical-binding.

* lisp/international/ja-dic-cnv.el: Use lexical-binding.
(skkdic-breakup-string): Remove unused var `kana-len`.

* lisp/international/latexenc.el: Use lexical-binding.
(tex-start-of-header): Declare.

* lisp/international/mule-diag.el: Use lexical-binding.
(list-character-sets): Remove unused var `pos`.
(list-character-sets-1): Remove unused vars `tail` and `charset`.
(list-charset-chars): Remove unused vars `chars` and `plane`.
(describe-coding-system): Remove unused var `extra-spec`.
(mule--print-opened): New var.
(print-fontset): Bind it.
(print-fontset-element): Use it instead of `print-opened`.

* lisp/international/quail.el: Use lexical-binding.
(quail-start-translation, quail-start-conversion):
Remove unused var `generated-events`.
(quail-help-insert-keymap-description): Use local dynbound var `the-keymap`.